#!/usr/bin/env node
const http=require('http'),
      url=require('url'),
      qs=require('querystring');
let items=[];
function genPage(){   
    let html=`<!DOCTYPE html>
        <html lang="en">
          <head>
            <meta charset="UTF-8">
            <title>Todo List</title>
          </head>
          <body>
            <h1>Todo List</h1>
            <form method="get" action="http://192.168.174.144:8080">
             <input type="text" name="item">
             <input type="submit" value="submit">
             </form>
            <ul id="items">
                  ${items.map(i=>'<li>'+i+'</li>').join('\n')}
             </ul>
           </body>
        </html>`;
        return html;

}
http.createServer((req,res)=>{
    let addr=url.parse(req.url);
    if(addr.pathname!=='/'){
          res.statusCode=404;
          res.setHeader('Content-Type','text/html');
          res.end('<h1>Not Found</h1>');
          return;
                        
    }
    let item=qs.parse(addr.query).item;
        //这个item是与input的name属性的值item对应
    if(item!==''&&typeof item !=='undefined')items.push(item);
    res.writeHead(200,{
      'Content-Type':'text/html',
      'Content-Length':Buffer.byteLength(genPage())
    });
      
    res.end(genPage());
}).listen(8080);
            

